Cylinder lock



Aug. 25, 1942. o. c. LARSON CYLINDER LOCK Filed'flct. 16, 1946 INVENTOR0770 61'L4H50A/ ATTOR EY Patented Aug. 25, 1942 UNITED STATES PATENTOFFICE CYLINDER LOCK Otto C. Larson, Brooklyn, N. Y.-

Application October 16, 1940, Serial No. 361,403

3 Claims. (Ql. 70421) This invention relates to cylinder locks employinga plurality of tumblers actuated by a key to bring the same into properalinement to provide rotation of the cylinder in opening or closing alock mechanism; and the object of the present invention is to provide alock structure of the character described having a series of keyblocking elements associated with the respective tumblers of the lock toprevent insertion of a normal key into the lock and further to renderthe picking of the lock more difficult; the invention further consistsin the provision of a key device associated with the lock having meansmoving the blocking pins or elements into inoperative position to permitinsertion of the key into the lock to actuate the tumblers thereof inthe operation of rotating the cylinder; and with these and other objectsin view, the invention consists in a lock structure of the class and forthe purpose specified, which is simple in construction and which isconstructed as more fully hereinafter described and as defined in theappended claims.

The invention is fully disclosed in the following specification, ofwhich the accompanying drawing forms a part, in which the separate partsof my improvement are designated by suitable reference characters ineach of the views, and in which:

Fig. l is a cross sectional view through a cylinder lock showing thegeneral relationship of the tumblers and the locking pins employed.

Fig. 2 is a section on the line 2-2 of Fig. 1 and also showing avertical edge view of part of the key for insertion into the lock.

Fig. 3 is a section substantially on the line 3-3 of Fig. 1 showing onlya part of the lock structure; and

Fig. 4 is a side view of a key looking in the direction of the arrow 4of Fig. 2.

In the drawing l represents the casing in which the cylinder ll of thelock is arranged. The casing has an enlarged disc or flange portion l2at its outer end, grooved as seen at 13 for mounting in any suitablelock casing or in an opening formed in a door or other support. Thecylinder H has a retaining plate I 4 at its inner end which retains thecylinder against longitudinal displacement in the casing and to thisplate is pivoted the usual spindle IS.

The casing It] has an upwardly extending web portion l6 having a seriesof bores or passages I! in which the backings [8 of the tumblers I9 arearranged, as well as the springs 20, normally urging the tumblersdownwardly into the key channel 2| of the cylinder. This channel is ofirregular cross sectional contour, depending upon the particular typeand kind of key 22 employed. In the present structure, however, thecontainer has on opposed walls, two inwardly extending ribs 23 and 24,and above the rib 23 is an inwardly set portion 25. The key 22 has onits upper edge the usual grooves or notches 25 which cooperate with thetumblers l9 in properly alining these tumblers in the cylinder I I so asto provide rotation of the cylinder when the key is properly inserted inposition. This construction is substantially conventional with looksthat are well known on the market,

In carrying my invention into eifect, I provide the cylinder l I with aseries of bores or passages 21 preferably arranged intermediate thepassages I 1. In these bores or passages are arranged key blocking pins28 normally held in extended position into the key channel 2| by springs29; the outer ends of which seat on retaining plugs 30 which simplyguard the springs from scratching or otherwise defacing the bore Illa ofthe casing H1 in which the cylinder ll rotates. The blocking pins 28 arepreferably arranged intermediate the tumblers l9 and may in fact beregarded as supplemental tumblers.

A lock of this construction will require the use of a speciallyconstructed key; that is to say, a conventional key which wouldotherwise fit the lock to operate the tumblers l9 will be blockedagainst insertion into the key channel 2| by the pins 28. I thereforeprovide on the inner end of the key 22 a beveled surface 3|, note Fig. 2of the drawing, so that upon inserting the pointed or beveled end 32 ofthe key into the channel 2|, the beveled surface 3| will operate to movethe blocking pins or supplemental tumblers 28 to the right as viewed inFig. 2 of the drawing, to allow the key to pass into the cylinderbeneath the tumblers I9. When the key is in fully inserted position, thenotches 26 will properly aline the tumblers [9 in the cylinder ll,allowing said cylinder to be rotated to actuate the spindle l5 inoperating a lock mechanism as in other locks of this type and kind.

It will of course be apparent that the blocking pins 28 also form stopslimiting the downward movement of the tumblers l9, and by changing theposition or arrangement of the pins 28 in the look, different eiTectsmay be produced in the entire lock structure.

With a cylinder lock constructed according to my invention, it willappear that the picking of a lock will be rendered more diflicult byreason of the necessity of having to care for displacement of each ofthe series of stopping or blocking pins employed while manipulating therespective tumblers.

In the present construction, which is shown to illustrate one adaptationof my invention, it will appear that the position of the blocking pinsor supplemental tumblers 28 is arranged above the flange 24 whichextends into the groove 33 formed in the key 22, and it is only thatpart of the key above the groove 33 which is beveled at the end 32 asshown at 3|. The lower portion 34 has the usual blunt end, as will alsoappear in Fig. 2 of the drawing. It will appear, however, that theparticular beveling can be arranged at any desired position on the keyto register with the particular location of the blocking pins orcylinder. It will also be apparent that any number of these pins may beemployed, and it is not absolutely essential that the pins be arrangedintermediate each of the tumblers of the look. It will of course beapparent that the inner ends of the pins 28 are slightly rounded orbeveled as are the inner ends of the tumblers to provide the outwardcamming of the pins 28 by engagement with the beveledsurface 3|.

It will be apparent that in locating the apertures 2.! intermediate theapertures 11, there is no possibility of the plugs 30 interfering withfree rotation of the cylinder H in the casing.

Having fully described my invention, what I claim as new and desire tosecure by Letters Patent is:

1. A cylinder lock of the class described havlongitudinally spacedtumblers operatively engagingone characterized edge of a key insertedinto the lock, another series of supplemental tumblers arrangedangularly to the first named tumblers and operatively engaging one sidesurface of a key inserted into the lock, said supplemental tumblersnormally extending transversely across the key into the lock, means atan end portion and along said side surface of the key in alinement withthe supplemental tumblers for displacing the latter in the insertion ofthe key into the lock, said supplemental tumblers being arrangedintermediate the first named tumblers, and each of said supplementaltumblers contacting two of said first named tumblers to support the samein raised position.

2. The combination with a cylinder lock employing tumblers and a key foralinement of the tumblers, of a series of supplemental tumblers at oneside of the cylinder and operatively extending across the key passage ofsaid lock between and operatively engaging pairs of said first namedtumblers, and means on said supplemental tumblers cooperating withspecial end and side surfaces of a key to provide for insertion of thekey and operation of the lock.

3. The combination with the cylinder of a lock employing tumblers spacedlongitudinally of the cylinder and entering the key channel of saidcylinder, of a pair-of supplemental tumblers arranged in the cylinderangularly to the first named tumblers at one side thereof andextending'into the key channel, and each of said supplemental tumblersbeing arranged intermediate and operatively engaging two of the firstnamed tumblers.

OTTO C. LARSON.

